What makes you YOU? Is it a single thing? or an alliance of upwards of 30 trillion things working together? According to an article in the April 2021 issue of Scientific American:
The human body replaces its own cells regularly. Scientists at the Weizmann Institute of Science in Rehovot, Israel, have finally pinned down the speed and extent of this “turnover.” About a third of our body mass is fluid outside of our cells, such as plasma, plus solids, such as the calcium scaffolding of bones. The remaining two thirds is made up of roughly 30 trillion human cells. About 72 percent of those, by mass, are fat and muscle, which last an average of 12 to 50 years, respectively. But we have far more, tiny cells in our blood, which live only three to 120 days, and lining our gut, which typically live less than a week. Those two groups therefore make up the giant majority of the turnover. About 330 billion cells are replaced daily, equivalent to about 1 percent of all our cells. In 80 to 100 days, 30 trillion will have replenished—the equivalent of a new you.
In a strange way, every human being, every animal, every plant is an alliance of micro particles. In my lifetime, I have given birth to and sloughed off untold trillions of tiny pieces of me. Yet I still see myself as a unified being with certain likes and dislikes, certain patterns of thought.
When it comes time for me to die, it’s like Better.Com firing 900 employees on a Zoom call. Except some 30 trillion parts of me would be abruptly cashiered—without benefit of unemployment compensation. I would like to think that my mental processes would continue somehow, but that’s getting into highly disputed territory.
So far my alliance has held together pretty well. The whole coronavirus situation has been like an invasive plant or insect species. Undoubtedly, I have ingested perhaps thousands, perhaps even millions of Covid-19 viruses, but never enough to disturb the majority population of the alliance, which, by the way, itself includes billions of non-threatening viruses of various sorts.
When you look at yourself as an agglomeration of tiny living things, it makes you feel humble. And it makes you laugh at a lot of the things that make people worry.
I feel good about myself because, as of now anyway, my 30 trillion parts are a kind of parliamentary democracy in which all the components still work together, peacefully for the most part.